MicroLED inspection - Page 2

Researchers from the UK-based University of Strathclyde, led by Dr. Eleni Margariti, developed a new microLED transfer process, based on a continuous, single shot roller transfer printing process.

The researchers say that this process can enable large-scale integration of microLEDs. The system they developed can transfer an array of 320x240 pixels (over 75,000 microLEDs) in a single shot, with sub-micron relative position accuracy. The transfer printing process preserves the array geometry with pixel spatial location error less than 1 µm deviation from the as-designed layout. 

The researchers also employed an automated sub-micron precision metrology system based on simple optical microscopy, to asses such large device populations and allow the assessment of yield.

InZiv announced a new industrial-level microLED inspection system, called the REL. The company says that this new system provides unprecedented speed wafer-level EL testing of microLEDs. The REL system can rapidly obtain EL measurements on a microLED wafer, with up to 6 million LEDs in 1 hour.

The company's unique technology offers repeatable, high- accuracy measurements, with no damage to the device. The system is fully compatible with both vertical and flip-chip designs. InZiv says that the REL offers the most critical and reliable microLED inspection on the market, enabling the advancement of all microLED applications. The company is already working on its next-generation system, which will double the output.

Korea-based Top Engineering developed and launched a new microLED chip inspection tool, offering non-contact EL inspection.

The equipment can analyze LED chips directly on the epiwafer, and inspect thousands of microLED chips at the same time. The tool can use non-contact EL inspection on vertical microLED chips.

We're happy to interview InZiv, as part of our series of interviews with MicroLED Industry Association members. InZiv develops testing and inspection equipment for display makers focusing mostly on MicroLED displays (but also QLED and OLED).

Q: Can you introduce your company and technology?

InZiv is a leader in display testing and inspection, providing high-resolution testing and inspection equipment to today’s foremost advanced display developers and manufacturers. InZiv’s proprietary nano-optical technology specializes in microLED displays, but also extends to QLED and OLED. With the size of pixels now reaching the single-micron scale, our testing equipment provides comprehensive data and nanometric resolution, empowering display manufacturers to improve their manufacturing processes, lower production costs, and enable greater access to the use of these displays by all consumers. Based in Israel, the company was founded in 2018, and counts a number of the world’s leading display manufacturers among its customers.

This is a sponsored post by STAr Technologies

With more and more mature technology for Mini- and Micro-LEDs fabrication, manufacturers are gearing up for the production phase and critically looking for more test efficiency and fast testing for the optical devices. STAr Technologies, as the leading Mini- and Micro-LEDs tester supplier continuously develops measurement technology to enhance optical testing capabilities and parallel test efficiency and to achieve cost-effective high-volume production.

Image: STAr Unicorn-LAIT II Tester Equipped EMI Shielded Test Environment

STAr’s Unicorn-LAIT II tester is designed to meet diverse industry requirements and to ensure accurate and reliable measurement results in the shortest amount of test time, based on an integrated parallel test architecture. The tester is ideal for electrical, optical measurement, driver functionality, RGB testing, etc. The tester is equipped with high efficient Dark and EMI Shield test environment dedicated to LED and Laser Applications. The system can be upgradeable with an autoloader for a fully automatic test with a cassette.

Today we're starting a new series, of interviews with MicroLED Industry Association members. The first company we interview is Radiant Vision Systems, and we have Shaina Warner, Radiant''s Marketing Program Manager.

Q: Can you introduce your company and technology?

Radiant develops and manufactures test & measurement solutions that are used to evaluate the visual quality of displays, backlit components, LEDs, other light sources. Using photometric and colorimetric imagers calibrated to a model of human visual perception, Radiant offers the most sophisticated inspection technology for ensuring light-emitting products meet customer expectations for quality and performance.

Leaders in consumer electronics, virtual & augmented reality, automotive, aerospace manufacturing, and beyond rely on Radiant to ensure accuracy, automate quality control, reduce costs, and improve efficiency. We have over 30 years of proven production experience with thousands of cameras testing millions of lights and displays worldwide. We’re also happy to be a global organization, offering direct local access to products and support that help equip our customers for success.

Q: Can you say why you joined the microLED association and what it is you hope to achieve?

This is a sponsored post by Applied Materials

Applied Materials Baccini Cell Systems provides advanced screen-printing solutions and systems for a wide range of applications - including for MicroLED production.

Here is an interview we conducted with Applied Materials' Director of Global Product Marketing, Daniel Hada, who details the company's solutions for MicroLED production and R&D.

Q: Can you tell us a little bit about Applied Materials' Baccini systems? What kind of systems are you offering?

We provide advanced screen-printing solutions for both R&D applications and high volume manufacturing. All Baccini systems are built for sheet-to-sheet printing, either on flexible or rigid substrates. In addition to our screen-printing capabilities, we also provide customers with different drying and curing solutions, in-line inspection systems to monitor the quality of the print immediately after the print, and fully automated print lines to enable low cost, and high volume manufacturing. Utilizing Baccini’s Esatto technology which provides high accuracy and high print repeatability, we developed the Double Print technology years ago, to allow print on print capability for printing narrow lines/small features with high aspect ratios and to minimize interruptions in the printed lines.

SAPIEN Semiconductors, based in Korea, is a fabless design company that provides innovative PWM CMOS backplane and μ-driver ICs for Micro-LED displays. The company utilizes its own patented technologies to achieve lower power consumption, lower leakage, better repairability and improved testability.

In the following interview, we discuss the company’s technology and business with its CEO, Myunghee Lee.

Q: Hello Mr. Lee, thank you for your time. Can you give us a short introduction to SAPIEN and your microLED technologies?

SAPIEN specializes in developing CMOS Backplane SoCs (System-on-Chip) for Micro-LED display applications. SAPIEN was founded in 2017 by industry veterans who have over 230 years of combined design experience in Display Driver ICs (DDI).

The founder and General Manager of Bolite Optoelectronics, Dr. Bowen Cheng, was invited to present at the recent Touch Taiwan 2021 Conference in April. The title of his talk was “Laser Processing Applications for the Manufacturing of Mini and MicroLED Displays.” Since it was presented in Mandarin only, microled-info.com caught up with Dr. Cheng to learn more about this trending subject and the company he started.

Q: Dr. Cheng, can you please tell us a little about your background, prior to starting Bolite?

I was a research engineer at Xerox PARC and helped develop surface micromachined microspring interconnects in a project funded by the U.S. Army Research in collaboration with Oracle. I was also a vital member of the team that successfully demonstrated the world's shortest wavelength diode laser at the time, a 250 nm UV laser for military applications. With these experiences in both semiconductor laser processing and MEMS processing, I decided to start Bolite and build a team to develop state-of-the-art laser solutions for microprocessing applications.

Q: I must admit I’ve not heard of Bolite before. What differentiates you from other laser microprocessing companies?

USA-based eLux was established in 2016 as a spin-off from Sharp Labs of America, to commercialize a unique MicroLED production technology. A year ago we discussed the company's technology and business with its CEO, Jong-Jan Lee.

Today eLux announced that it has installed an automated fluidic assembly tool at its prototype fab in Taiwan. The new tool features fully automatic cassette-to-cassette fluidic assembly of ten display panels, each up to 15-inch in size. The tool has provisions for capture and recycle of microLEDs and assembly fluids to minimize operating costs, and its capacity can be expanded by adding two additional modules.